. It’s up to you to decide whether to _____ physics or chemistry.
It was in Beihai Park _____ they made a date for the first time ______ the old couple told us their love story.
.Only when your identity has been checked ________.
More and more people are beginning to _____ importance to living a low-carbon(低炭) life.
The number of people visiting the exhibition ______ 50, and a number of them ____ painters.
Although it’s at ____ dusk, the children don’t get tired of playing ____ football outside.